I wonder if someone could help me out with an issue I'm experiencing trying to get my site up and running on Goddaddy.
I'm trying to get extension-less url rewriting working using the ManagedFusion Rewriter (http://www.codeplex.com/urlrewriter/) Unfortunately I'm getting the following error:

Server Error in '/' Application.
Security Exception
Description: The application attempted to perform an operation not allowed by the security policy. To grant this application the required permission please contact your system administrator or change the application's trust level in the configuration file.

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

@bshacklett there is nothing wrong with fixing issues with new version but I wish microsoft would use more understandable error messages intead of very long non-sense messages
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dvdmnJan 27 '14 at 21:33

One cause for this problem is when you have done the totally odd thing of publishing you application on the server by using the server to download the application from the Internet. The files will then be marked as originating from the Internet, and security settings then prevent them from running.

This is actually a known issue with GoDaddy's Medium Trust environment. However with the latest release of URL Rewriter 3.0 all these issues are now gone. Please get the latest release and let me know if you have any issues.

I had a similar issue with GoDaddy. Even though it didn't seem related at first since it's not in the stack trace (and may not apply to you since you're using third party code), removing Response.End() calls solved the issue in my case.